diff --git a/InformationEntityOntology.ttl b/InformationEntityOntology.ttl
index 0821bd6f..d615b345 100644
--- a/InformationEntityOntology.ttl
+++ b/InformationEntityOntology.ttl
@@ -1880,6 +1880,14 @@ cco:InternationalAtomicTime rdf:type owl:NamedIndividual ,
                             rdfs:label "International Atomic Time"@en .
 
 
+###  http://www.ontologyrepository.com/CommonCoreOntologies/InternationalGeomagneticReferenceField
+cco:InternationalGeomagneticReferenceField rdf:type owl:NamedIndividual ,
+                                                    cco:GeospatialCoordinateReferenceSystem ;
+                                           cco:definition_source "Alken, P., Thébault, E., Beggan, C.D. et al. International Geomagnetic Reference Field: the thirteenth generation. Earth Planets Space 73, 49 (2021). https://doi.org/10.1186/s40623-020-01288-x , https://www.iaga-aiga.org/" ;
+                                           rdfs:comment "This global main field model provides magnetic field values for any location on Earth, e.g. for  navigational purposes (declination) or as a standard for core field subtraction for aeromagnetic surveys. An updated version is adopted by International Association of Geomagnetism and Aeronomy (IAGA) every 5 years)."@en ;
+                                           rdfs:label "International Geomagnetic Reference Field"@en .
+
+
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/InternationalTerrestrialReferenceSystem
 cco:InternationalTerrestrialReferenceSystem rdf:type owl:NamedIndividual ,
                                                      cco:GeospatialCoordinateReferenceSystem ;